Apparatus for drying and superheating of steam in locomotive boilers



Aug. 11, 1926. 1,596,072

A. ANDERBERG APPARATUS FOR DRYING ANII SUPERHEATING OF STEAM IN LOCOMOTIVE BOILERS Filed Sept. 1. 1923' 3 Sheets-Sheet 1 alli/z Aug. 17; 1926. 7 1,596,072

' A. AN'DERBERG I APPARATUS FOR DRYING AND SUPERHEATING OF STEAM-IN LOCOMOTIVE BOILERS Filed Sept. 1923 3 Sheets-Sheet 2 WW 1%; my I A. ANDERBERG APPARATUS FOR DRYING AND SUPERHEATI'NG OF STEAM IN LOCOMOTIVE BOILERS.

Filed Sept. 1. 1925 3 sheets-sheds Que)? Zarfl J/uriw 1691:

Patented Aug. 17, 1926.

ANDEBS ANDERBERG, OF MALMO, SWEDEN.

APPARATU$ FOR DRYING AND SUPER-HEATING F STEAM IN LOOOMOTIVE BOILERS.

Application filed September 1-, 1923, Serial No.,660,603, and in Sweden October 20, 1922.

This invention relates to an apparatus for drying and superheating of steam in locomotive boilers. The object of the invention The invention differs both in respect to the system and to the construction employed from superheaters as heretofore designed for use in locomotives. As well known the locomotive boilers having superheaters must be constructed and built in a special manner, so that a correct relation s obtained.

between the furnace, the boiler tubes and the superheater, because the heat supplied to the superheater is taken from the com-v bustion products before the latter have left the tubes, that is to say the heat required for the .superheating must be'produced in the boiler specially for this purpose in addition to the heat required for producing saturated, wet steam of the same pressure.

According to this invention the drying and superheating of the steam is however; obtained by employing exclusivelyorsub stantially such heat as cannot be utilized in the boiler furnace and therefore otherwise would pass away into the atmosphere through the smoke stack.

installed'in old locomotive boilers without any modification whatsoever of the furnace or the heating surface, and obviously a con-. siderably increased effect in, such boilers is thereby obtained withoutanyinc rease what-' ever of the fuel consumption, or vice versa for the same developed effect as before the installation of the apparatus. accordingflto the invention, the water consumption and reduced because. the engine driven by the boiler may work with considerably smaller cut-off than before. I

In the drawings: Figure l is a central longitudinal section through the' smoke box. of a locomotive boiler provided with an apparatus accord.

in to the invention. I p igure 2 is a horizontal section taken on at ig. 1.

For this reason the new appara-tusmay be thus the coal consumption are considerably" said colls.

Figure 3 is a horizontal section taken on line-33 of Fig. 1.

Figure 4 is a central longitudinal section through the smoke boX of a locomotive boiler provided with the new apparatus showing a further development of; the invention.

Figs. 5, 6, and 7 show modified arrangements of the throttling member.

The apparatus consists of a suitable number of coiled pipes 1, 2, 3, 4, 5, 6, 7, 8, 9, 10

arranged coaxially in relation to each other and also coaxially in relation to the smoke stack 36 immediately underneath the lowest end of the same and in such a manner, that the turns of adjacent coils are offset in relation to each other as well laterally as vertically. The upper ends of the coils open into a collector chest 37 connected by means of a vertical pipe 11 with the main steam 7 pipe 17 of the boiler. The said pipe 11 has a flattened sectional area, as shown in Figure 2, so that the same, being arranged on the outside of the outermost coil 10, may take up as little space as possible in radial so direction between said coil 10 and the wall of the housing 13 arranged on top of the smoke box and surrounding the new apparatus. 1 In a similar manner the lower ends :of the coils open intoanother collector chest 14 connected with the steam pipe 15 leading to the cylinders of the locomotive engine. Thecoils are held in theirplaces by means of frames 16 fixed to the wall of the housing 13, by means of suitable stays andbolt '00 and nut devices 41. The combustion products leaving the tubes 18 ofthe boiler are prevented from directly passing between the blast pipe 19 and the innermost coil by means of aplate or the likef20 of suitable form'surroundingsaid blast pipe 19. All the combustionproducts are thus forced to pass between the different turns of all coils, so that the largest possible amount of heat is transferred to the steam passing through 1 As obviously according to the arrangement of the coils shown in the drawing the lengths of said coils will vary, that is to say 7 the inner coils will be shorter than the outer ones as long as the number of turns in each coil is the same, in like manner. the steam passing through said coils will besubjected to less resistance in th inner coils than in the outer ones, which results in certain $5.15 1119 ferences between the drying and superheating efl'ects in the various coils. This disadvantage may obviously be avoided by giving the various coils different sectional areas, as indicated for example by dotted lin s in connection with the pipe ends merging into the collector chest ll, see Fig. 1, but it is also possible to use pipes ot the same diam eter for all the coils provided the openings of certain coils are throttled by means of suitable devices at one of the'collector chests. Figures 3, 5, 6, and 7 show different designs for the realization of such throttling. The lower collector chest 14, which at one end is provided with a. flange 21 to facilitate the fixing of the same to the steam pipe 15 leading to the engine ylinders, is provided with a simplified device for the indicated purpose. Plugs 22 are in a known manner screwed in the wall of the collector chest opposite to that into which. the coils open. lVhen removing these plugs 22 the corresponding tube end becomes accessible from the outside. In order to throttle the opening of the coil 2 the plug 22 is provided with an extension 23 which extends into the opening of the tube 2 whereby the passage area'of the opening is diminished to a suitable extent by means of the member 2a. The plug for the pipe 1 is provided with a similar member 24 but of somewhat larger diameter, whilst the plugs for the pipes 3 to 10 have throttling member 24:. of less and less diameter or no throttling device at all.

Instead of making the throttling member in one piece with. the plug the same may either be screwed in as shown at 23 as in Fig. 5, or be arranged on a special pin 25 which is screwed in the plug 22 and which may be adjusted to take up the correct position. in relation to the opening of the pipe by means of a lock nut 26, as shown at the coil 6, Figure 6. The throttling means may also have the form of a conical shutting member 27, as shown at the pipe 8, Figure 7, said shutting member 27 being screwed on the end of the extension of the plug 22 and arranged to be held by means of alock nut 28 in different positions in relation to the opening of the pipe for adjusting the area of the latter. The adjustment of the throttling members in relation to the ends of the pipes is carried out in the factory before assembling the parts of the apparatus, and

the latter being once installed in the smoke box of a locomotive the means for adjusting the throttling iembers are not accessible from the outside.

Referring to Figure 4 a further development of the invention consists in an arrangement whereby the steam does not di-' rectly pass from the collector chest 14; to the engine cylinders, but passes first through special pipes 29 arranged within a corre-- sponding number of the upper boiler tubes 30. The pipes 29 have a double bend in the tubes 30 and are with their free ends con- .nected to special steam collectors 31; the one side of which is in communication with the collector chest ll and'the other side with the main steam pipes 15 leadin to the engine 0 cylinders. The boiler tubes 30 having superheating tubes 29 are for this purpose of boiler but not to a steam drying apparatus comprising coils arranged coaxially around the smoke stack of the locomotive. The device illustrated in Figure further offers the advantage that the heat of the combustion products, that passes through such boiler tubes 18 which are not provided with superheating tubes, is completely utilized in heat ing the coils arranged coaxially around the smoke stack, whilst in the older superheat ing devices this heat was allowed to pass through the smoke stack without any utilination whatsoever. The construction shown in Figure l has the advantage that the superheat-ing tubes 29 may be formed beforehand to the correct shape and their ends provided with a flange may directly be fastener by means of studs and nuts to the special steam collector 31. This steam collector 31 has a partition 33 dividing the same into two chambers, of which the one 31 communicates with the collector chest 14 and the other 35 with the main steam pipe or pipes 15 leading to the cylinders.

The combination of the pipes 1 to 10 for drying the steam in the smoke box with the superheating tubes 29 in the boiler tubes 30 is of extraordinary advantage. It is not the intention to obtain a pronounced superheating by the coils in the smoke box, since the main object of these coils is substantially to dry the steam. This steam thus dried may however in a most economical manner be superheated to a very great extent in the double bent superheating tubes.

It may also be pointed out that in general it is practically impossible to adapt such double bent superheating tubes in connection with a system of pipes arranged in the smoke box, if this system did not consist of steam chests and coils connected in parallel, such as shown in the present invention, because otherwise the losses in pres sure in the pipe system and the impossibility of forcing would prove an unsurmountable obstacle.

Having thus described my invention what I claim and desire to secure by Letters Patent is I 1. An apparatus for drying and superheating of steam in locomotive boilers fired lOO by forced draught caused by exhaust steam from the engine, comprising in combination a smoke box and a smoke stack arranged thereon, a number of coiled pipes arranged coaxially in relation to each other and to said smoke stack, a hollow central member surrounded by the coiled pipes and arranged in vertical extension below the smoke stack, said central member having open sides so that the smoke may enter into the same substantially along its whole length, a steam exhaust pipe connected to the lower end of said central member and exhausting steam through the same and the smoke stack for causing the forced draught, an upper and a lower collector chest between which the coiled pipes are connected in parallel and means for giving the shorter inner coils less free steam passage than the outer coils.

2. An apparatus of the kind described, comprising in combination a smoke box and a smoke stack arranged thereon, a number of substantially parallel coiled pipes forming steam passages and arranged coaxially in relation to each other and to the smoke stack, a hollow central member surrounded by the coiled pipes and arranged in vertical extension below the smoke stack, said central member having open sides so that the smoke may enter into the same substantially along its whole length, a steam exhaust pipe connected to the lower end of said central member, an upper collector chest consisting of substantially horizontal and vertical parts in free communication with each other, means for connecting the upper ends of the coiled pipes to said horizontal part and means for connecting the steam inlet to said vertical part, a lower collector chest to which the lower ends of the coiled pipes are connected, means on said lower chest for connecting the steam outlet thereto and means for giving the inner coils less free steam passage than the outer coils.

3. An apparatus of the kind described, comprising in combination a smoke box and a smoke stack arranged thereon, a number of coiled pipes forming steam passages and arranged coaxially in relation to each other and to the axis of the smoke stack, a hollow central member surrounded by the coiled pipes and arranged in vertical extension below the smoke stack, said central member having open sides so that the smoke may enter the same substantially along its whole length, a steam exhaust pipe connected to the lower end of said central member, an upper and a lower collector chest between which chests the coiled pipes are arranged in parallel, means forgiving the inner coils less free steam passage than the outer coils, means on the upper chest for connecting a steam intake to the same, an extension on the lower chest and a steam outlet connected to said extension which comprises two separate chambers connected with each other by means of superheating pipes extending into a number of enlarged fire tubes of the boiler.

In testimony whereof, I have signed my name to this specification.

ANDERS ANDERBERG. 

